Stencil



Jian. 311, 1939.A

H. F. ELLIOTT STENGIL Filed Jan. 3l, 1938 Patented Jan. 31, 1939 UNITED STATES ATENT OFFE l Claim.

This invention relates to stencils particularly adapted for use in connection with an addressing machine where a vertical stack of stencils is contained in a holder from which they are advanced in succession toward an addressing position.

The stencil with which this invention is particularly concerned comprises a stiff rectangular frame of paper stock having a window therethrough, the frame also having a thin welt sheet which projects into the aoresaid window and of itself has a window and thereby forms a peripheral ledge or strip on which an address-receiving stencil sheet is adhesively affixed, the

l sheet lying within the rst window and within the opposite faces of the frame.

In the addressing'machine the successive lowermost stencils are moved endwise out of the stack towards the addressing position. It sometimes happens that the welt strip that supports the stencil sheet is caused to buckle so that the middle part of the inner edge thereof is raised above the face of the stencil and hence can catch against the edge of the window of the next uppermost stencil of the stack.

It is an object of the present invention to provide a stencil with a welt strip so arranged that the edge thereof cannot project above the face of the stencil.

A further object of the invention is the provision of a stencil having a welt strip that is so narrow where the buckling is greatest that the edge thereof is not liable to rise above the face of the stencil.

Another object of the invention is the provision of a welt strip with a free edge which is tapered in both directions from the opposite sides of the window towards the middle thereof so that any projecting buckled edge of a welt strip is wiped down below the face of the stencil as the edge passes over a superimposed stencil.

Another object is generally to improve the construction of stencils.

Fig. l is a plan View of a stencil embodying the present invention.

Fig. 2 is a reverse View of the stencil of Fig. 1.

Fig. 3 is a sectional view taken along line 3--3 of Fig. 1.

Fig. 4 is a longitudinal section taken along line 4--4 of Fig. l.

The stencil herein illustrated comprises a rectangular frame l composed of a thin intermediate welt sheet l2 combined between and with thicker facing sheets i4 and I6, all three sheets being composed of paper stock. Aligned windows I3 and 2li are formed in the facing sheets lli and l5, the window 2li being larger in all dimensions than the window I8.

A window 22 is formed in the welt sheet, the window 22 being smaller than the aforesaid win- 5 dows so that a peripheral welt strip section 2t of the welt sheet projects into both windows of the facing sheet.

A thin address-receiving stencil sheet 26 occupies the window 20 and is secured to the welt 10 strip 2li over the Window 222 in the welt sheet.

As generally used, the stencils are stacked in the addressing machine, and advanced endwise from the stack, with the stencil sheet uppermost, as illustrated in Fig. l. In one type of 15 machine, however, the stencils are stacked and advanced inverted 0r with the stencil sheet underneath and the welt strip uppermost, as illustrated in Fig. 2. As used with this type of machine, there is a possibility of the trailing side 20 of the welt strip of the lowermost stencil catching uponthe edge of the Window of the next uppermost stencil of the stack as the lowermost stencil is moved out of the stack with a severely buckled welt strip. 25

In accordance with the present invention the short sides 2S of the welt strip,` One of which sides may be the trailing side as the stencil is advanced, instead of being formed with straight inner edges, as indicated by the dotted 30 lines 3G, Fig. 1, are formed with inclined edges 32 forming an obtuse angle and which start from the long sides of the strip and which meet in the longitudinal line of the stencil so that the width of those parts 3i of the welt strip lying 35 in the median line of the stencil and that project inwardly of the windows of the facing sheet are materially less than the parts 36 which confront the long edges of the stencil.

As has been stated heretofore the stencil some- 40 times tends to buckle. The buckling usually is caused by the expansion of the stencil sheet and causes the sheet sometimes to rise upwardly above the top face of the stencil frame, as indicated in Fig. 4, thereby raising the middle part of the narrow edges of the welt strip. The buckling of the narrow edges is greatest in the longitudinal line of the stencil and is the least adjacent the long edges. The angle of the edges 50 32 is such that the width of the welt strip is not enough to permit the inner edge of the section to project above the top face of the stencil frame. Thus the welt strip ofthe lowermost stencil of a vertical stack of such stencils is 55 not liable to catch upon the upper stencil as it is moved from the stack.

The edges 32, being at an angle to the line of movement of the stencil tend to be forced downwardly by movement in Contact with an upper stencil, rather than to catch thereon in the unusual instance that the buckling is so severe as to position the edges above the face of the stencil or if the upper stencil should be bent downwardly.

I claim:

A stencil comprising a welt sheet combined with and between thicker frame sheets, both frame sheets having aligned frame openings therethrough exposing the welt sheet, the welt sheet having an opening therethrough registering with the aforesaid windows and smaller than said windows whereby the Welt sheet projects continuously over the frame windows, and a stencil sheet in one frame window affixed onto the welt sheet over the window therein, one side edge of the welt sheet being narrowest in the median line of the stencil and widening progressively on opposite sides of the median line, the welt sheet being narrowest where the buckling is greatest and widest where the buckling is least and the Width of the welt sheet at -any part of said edge being insufficient to project above the face of the stencil when the stencil sheet is buckled.

HARMON P. ELLIOTT. 

